This invention relates to radiation detectors such as those used in detection of radon gas which record the impact of alpha particles. More particularly, this invention relates to packaging for such detectors during handling and irradiation exposure.
As described, for example, in U.S. Pat. No. 3,665,194 (Alter et al, 1972) devices for detection of radon gas have been developed in which the radon gas is detected by exposure of a film of detector material coated on one face of a conventional glass microscope slide or in the form of a separate sheet of material which is cemented or secured to a base plate. The detector material is exposed to irradiation by alpha particles emitted by radon gas and the detector material has the property of forming damage tracks along paths traversed by the alpha particles. After exposure, the material is etched with a reagent to enlarge the tracks for convenient counting. Typically, the detector is exposed only at the location for which a radiation monitor is to be evaluated in order to avoid "background" irradiation not associated with that location. Consequently, the detector material must be shielded from irradiation during handling and transport to the location to be monitored, and similarly shielded following the monitoring exposure, particularly when subsequent processing such as track etching is performed at a different site to which the detector must be again transported.